The South American country defaulted on its debt, according to a statement issued Monday night by S&P Global Ratings. The agency said the 30-day grace period had expired for a payment that was due in October.

A debt default risks setting off a dangerous series of events that could exacerbate Venezuela's food and medical shortages.

If enough holders of a particular bond demand full and immediate repayment, it can prompt investors across all Venezuelan bonds to demand the same thing. Since Venezuela doesn't have the money to pay all its bondholders right now, investors would then be entitled to seize the country's assets – primarily barrels of oil – outside its borders.

Related: Trump administration bars U.S. banks from some Venezuelan debt

Venezuela has no other meaningful income other than the oil it sells abroad. The government, meanwhile, has failed for years to ship in enough food and medicine for its citizens. As a result, Venezuelans are waiting hours in line to buy food and dying in hospitals that lack basic resources.